Nomenclature
warhead
Complette round length (in.)
Complette round weight (lbs)
Color coding
M267
blue with white markings/brown band
M261
OD with yellow markings
WDU-4A/A
M255A1
Flechette
54.6
20.2
OD with white markings and diamonds
M257
Illumination
M278
IR Illumination
M229
HE Long
62.8
27.9
OD with yellow markings
M151
HE
54.7
20.8
OD with yellow markings
M274
practice smoke charge
52.8
20.8
blue with white markings
M156
White Phosphorus
52.2
20.6
light green/yellow band/red markings
WTU-1/B
practice solid
52.8
20.8
blue with white markings
M264
White smoke
MK66 rocket motor
MK40 rocket motor
CHARACTERISTIC
MK 66
MK 40
Length without warhead
41.7 inches
39.3 inches
Motor burn time (77F)
1.05 - 1.1 sec.
1.55 - 1.69 sec.
Average thrust
1,300-1370 lbs.
720 lbs.
Average spin rate
9 - 10 rps
1 rps
Motor burn out
1280 feet (397 m)
1460 feet (445 m)
Velocity at motor burnout
2425 fps
1965 fps
Maximum range
10,425 meters
8,080 meters
spin-stabilized
fin-stabilized